On Tue, Sep 04, 2012 at 11:10:54AM -0700, H. Peter Anvin wrote: > On 09/04/2012 10:59 AM, Josh Triplett wrote: > > > >Unfortunately not. We need enough of ACPI available to go read the > >BGRT to know what to copy, so we need to defer freeing boot services > >code until after we initialize ACPI (and thus everything ACPI needs, > >which includes EFI since ACPI looks for root tables there). > > > >>I wouldn't be surprised if some implementations got really cranky if > >>we accessed boot services data after we installed a new virtual memory > >>map. > > > >Note that I've carefully accessed the boot services data *through* the > >new virtual memory map, which should work fine. > > > > There are some platforms which have bugs in this area, so there are > other reasons to defer freeing up boot memory until as late in the > boot process as we can possibly get away with. > > free_initmem() is presuambly the place that makes most sense. You're suggesting a call from free_initmem() to efi_free_boot_services()? Or, from init_post() right before the call to free_initmem()? > This > is EFI-specific but not x86-specific, let's not commingle those > concepts, please... init/main.c already calls the x86-specific efi_enter_virtual_mode (defined in arch/x86/platform/efi/efi.c), and I split the call to the x86-specific efi_free_boot_services out of that. Neither of those functions exists on non-x86 platforms, and thus I mirrored the #ifdef currently wrapped around efi_enter_virtual_mode for the new call to efi_free_boot_services. While it might make sense for that code to exist on non-x86 EFI platforms, it currently doesn't. At best, I could add static inline stubs to linux/efi.h for those functions to avoid the ifdefs, but as far as I can tell the same issue applies to quite a few more functions in efi.h. Would you like me to add the static inline stubs for the couple of functions called from init/main.c, or leave the #ifdefs? - Josh Triplett -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
